The University of Strathclyde - Energy Infrastructure Project

This project saw us deliver an unusual hybrid of above and below ground district heating network.  This solution was necessary to avoid clashes with existing services, but also to navigate the existing buildings on the campus.

Below ground we installed 2.2km of Series 2 Logstor steel pipework.  This ranges from 400/630mm down to 80/160mm and involved 664 below ground welds and 617 below ground joints.  This is an unusually high number of welds and joints and reflects the work needed to avoid clashes with existing utilities and buildings.

We also undertook thrust boring works, enabling 2No 700mm diameter sleeves to pass below one of Glasgow busiest vehicles route (Cathedral Street) This allowed us to extend the district Heating serving the University new state of the art sports facility along with other existing buildings.

We also installed over 800m of District Heating that had to be above ground to overcome existing restrictions and services that were assessed as too high a risk with underground pipework in a city centre location. The above ground pipework is a combination of fully welded and the use of a Victaulic jointing system with thermal insulation and cladding.

During the surveying period it became clear that the building, which was built circa 1970’s had several issues which would need to be addressed to get it to the standard required for a 21st century energy centre.  The most significant issue was that the plant room would be situated above a basement.  Flooding and water damage had impacted the structural integrity of the basement and this needed to be remedied.

The primary support structure in the basement was a concrete encased steel frame. Over the years the exposure to water had caused the concrete to degrade which had also caused degradation to the steel.  It was essential to the structural integrity of the building that this frame was repaired, so it was stripped of concrete to expose the steel beams.  These had plates welded, where necessary, to strengthen them and were then covered by a waterproof resin.

The equipment which would sit above the basement was extremely heavy, with some individual items weighing upwards of 25 tonnes.  After calculating the exact loads, our in-house architectural technologists added additional steelwork to the basement including a series of frames and individual columns.

Another issue which faced our team was getting enough ventilation into the plant room to meet legislation.  Our designers were able to convert the existing windows and skylight into ducts and louvres.   Similarly, noise, was an important issue for the University and Vital were able to create a range of attenuation solutions, which included acoustic louvres and an acoustic enclosure for the CHP engine.  These measures combined to ensure that the noise emissions were within acceptable levels.

We commissioned an in-depth flue dispersion model to ensure air quality standards were met and this demonstrated that we would need to install flues 5m higher than the existing ones.  The chimney the flues were attached to was part of The Royal College which is a listed building and this meant that we would need to get consent to perform the work.  Once permission was granted we installed the flues within a steel frame and then used an innovative fibreglass, brick effect cladding to ensure its appearance was in-keeping with the surrounding building.

In addition to the core, structural work, the University also wanted Vita Energi to perform several other upgrades.  This included creating an access route from the John Street Entrance to the Montrose Street entrance.  We worked with the client to create a high-level corridor, 6m above the boiler house.   Legislation required that the corridor would provide fire resistance for 2 hours and the university requested it include viewing panels.

Phase 1 & 2 of the project had been finalised, but Phase 3 was still in the planning phase and the heat loads were not yet known.  We therefore needed to design a flexible solution and replaced the professional team’s design of two 2.2MWe with a single 3.3MW CHP engine.  This, alongside the boilers and thermal store would meet the initial peak demand, with the option to install more CHP capacity as needed at a later date.

Due to the city-centre location, deliveries and removals of the existing plant was problematic and saw us utilising two cranes.  The first involved a smaller 132-foot crane which lifted the dry air coolers onto the roof and then removed the old 1970’s boilers which weighed 27 tonnes each.  The team then set up a 100m high crane capable of lifting 400 tonnes.  The larger crane was able to reach over The Royal College building to where the chimney is located and remove the existing flue, which was cut into sections and disposed of before the new flue lining was installed.